Wet/dry vacuum cleaning systems are commonly used in commercial, industrial, and residential settings for cleaning and purging various types of drains and equipment, including piping, plumbing fittings and fixtures, drain and filter conduits, and many other fluid carrying systems, components and lines. Vacuum (suction) or positive pressure is normally applied by the system through lines. The lines typically are secured to a fitting, which connects the line with the drain or other area to be cleaned or purged.
The fittings now in use, regardless of their shape and irrespective of their means of attachment, each can only accommodate a line of a single diameter. A particular diameter fitting must be used with the same diameter sized line. This, of course, requires that many different fittings be provided with a given cleaning system which uses multiple sized lines. This results in the added expense of purchasing fittings and the inconvenience of transporting multiple fittings to a worksite or discovering that the right sized fitting is missing for the job at hand.